Improvement in rotary steam-engines



PA'IEN HENRY TAYLOR, on BALTIMORE, MARYLAND.

IMPROVEMENT IN ROTARV STEAM-ENGINES.

Specification forming part of Letters Patent No. 137,261, dated March25, 1873.

To all whom it may concern.-

Be it known that I, HENRY TAYLOR, of the city and county of Baltimoreand State of Maryland, have invented certain new and useful Improvementsin Steam-Engines, of which the following is a specification:

This invention relates to a steam-engine in which a rotary movement ofthe hub which carries the steam-cylinders is derived from thereciprocations of the pistons within said cylinders acting upon inclinedfaces of a stationary case surrounding the said hub and cylininderswhich it carries.

The nature of my invention and the manner in which the same is or may becarried into effect will be understood by reference to the accompanyingdrawing, in which- Figure 1 is a plan view of the engine partly insection. Fig. 2 is a vertical central section of the same.

The principal elements of the engine are as follows: First, a series ofsteam-cylinders, B, carried by and radiating from the axis of revolutionof a hub or drum, A, and receiving steam at their inner ends only.Second, pistons 0, one for each cylinder, pressed outwardly at theproper times by steam admitted to the inner ends of the cylinders, andprovided with rods or extensions 0, to project beyond the outer ends ofthe cylinders. Third, a surrounding case, D, provided with a series ofinclined faces, against which the rods or extensions 0 of the pistonsact to put and maintain the drum or hub A in revolution. Fourth, steamchest and valves toadmit and exhaust steam at the proper times andintervals into and from the cylinders.

The wall of the case D is undulating, approaching and receding atregular intervals from the center of the case, and forming a series offaces or inclines, over which the parts C travel. Steam is admitted toeach cylinder when its rod 0 reaches the top of each incline, and then,the steam pressure, acting on the piston, causes the outer end of thesamethat is, the part O-to travel down the incline,

thus effecting at each outward impulse of each piston a partial rotationof the hub or drum to which the cylinders arefixed; and by so arrangingthe cylinders that there shall always he one or more which is thus aoting, the

hub and its cylinders will be kept in constant rotation so long as steamis let on.

In an engine of this kind the number of cylinders employed may vary. Ihave found that aproper result cannot well be produced with less thansix cylinders--that is, three pairs-- and I prefer to use eight, ten, ormore cylinders, depending upon the diameter of the engine. In thepresent instance I have shown four pairs of cylinders, the two cylindersof each pair being placed diametrically opposite each other, receivingand exhausting steam synchronously.

I shall now proceed to describe more in detail the construction of theengine.

The hub A is mounted to revolve in the case D, being provided with acentral shaft, D extending through a proper bearing in the bottom of thecase, and carrying on its outer end a wheel, D from which power may betransmitted to any machinery which it is desired to put in motion. Thedrum or hub is provided with steam-cylinders B, eight in number,radiating from the axis of revolution of said drum or hub, and arrangedto receive,

steam through ports a from the interior of the hub, which constitutesthe steam-chest. The cylinders may be cast in one piece with the hub, ormay be formed separate therefrom and then attached in any suitablemanner. I prefer the former arrangement. To stiffen the cylinders theymay be cast with braces or a skeleton frame-work, connecting andsupporting them. Each cylinder is provided with a piston, O, which maybe of any suitable construction, and packed, as is usual withsteampistons, so that it may work steam-tight within the cylinder. Thepiston is provided with an extension or arod, G, extending out throughthe outer and open end of the cylinder, and designed to work against theseries of inclines on the case D. For the purpose of reducing friction Iprefer to place in the end of the part 0 a friction-roller, 1);. and inorder to prevent the piston from turning in the cylinder and thus movingthe roller from its proper position, I provide the part 0 with aguide-pin, 0, working in a slot, d, in the outer part of the cylinder.The cylinders are arranged to work in pairs, the two cylinders of eachpair being "placed diametrically opposite each other, as

shown. They are surrounded by a case, D, whose wall against which therollers I) work, is undulating or made up of a series of faces, arrangedsubstantially as shown. These faces may be described as follows: Thefaces 1 are struck on a circle whose radius is about equal to thedistance between the axis of the hub A and the outer extremity of anyone of the rollers b, when the piston of that roller is at its innermostposition. The faces 3 follow a circle of a radius equal to the distancebetween the axis of the hub and the outer extremity of any one of therollers b when the piston of that roller is at its outermost position.The inclined faces 2 and 4, which connect the faces 1 and 3, havepreferably a'cycloidal curve,

- their outward inclination or curve being greatest where they adjointhe faces 1. The pistons perform their work on the faces 2 or 4according to the direction in which the cylinders revolve. If, forinstance, the revolution be in the direction of the arrow in Fig. 2,then the impulse is derived by the successive travel of the pistonsoutwardly over the faces 2.

Ido not, of course, limit myself to this specific formation of thesefaces, as in this respect they may be varied to a considerable extentwithout departure from the principle of my invention. They should,however, be so formed and connected as to prevent the formation of anyabrupt angles or corners which would be apt to produce irregularity ofmovement and wear; and as concerns the size or length of the faces,

they should be so proportioned that before orat the time the piston-rodsof one pair of cylindershave reachedthe outer end oftheir stroke therods of another pair will be beginning their outward movement, so thatat all times there will be at least one pair of pistons exerting theirforce to drive the engine.

The admission and discharge of steam into and from the cylinders isregulated by means of valves E, six in number, located within the hubAand arranged in pairs, as shown. In each pair of valves anexhaust-channel, e, is formed,which channel opens through the face ofeach valve and communicates through a tubular stem,F, on which each pairof valves is mounted with the exhaust-pipe G. A plan and front elevationof the double valve is shown in Fig. 3. The stems F radiate from thecenter of the case D, and the valves are placed at equal disastuffing-box on the cover or top of the steam- -chest B, and its lowerend is stepped in the base of the chest, as shown. This pipeand thevalves are designed to remain stationary while the cylinders and hub orsteam-chest re= volve. Steam is admittedinto the bodyof the chestthrough a'smaller pipe, H, arranged concentrically within exhaust-pipe Gand opening at its lower end through the exhaust-pipeinto thesteam-space, as shown in Fig. 2. The exhaust-pipe G can, however, berotated to vary the position of the valves, to cutoff steam sooner orlater, as desired, or to reverse the engine. Asimple device for thepurpose is shown in the drawing. It consists of a lever, I, fast at oneend to the pipe G and with its outer end extending over an uprightframe, J, on one side of the engine, seen in Fig. 2 and in dotted linesin Fig. 1. Two pins,ff, 0n the top of the frame indicate the extremepoints to which the lever can be moved. Then the lever rests against pinfthe engine will revolve in the direction of the arrow in Fig. 1,- andsteam will be admitted during the entire, or nearly the entire, strokeof the piston. When the lever rests against pin f the engine will bereversed with full admission of steam, as before By moving the leverslightly away from these points toward the center of the frame steam canbe cut offat any desired point. In the drawing the lever is representedas adjusted to cut off steam at from two-thirds to threefourths stroke.It will be noticed that the faces 1 of the case D'permit this cut-off,and are de signed for the purpose. The sooner steam is admitted to thecylinders after their pistonrods reach the faces 1 the sooner will steambe cut off during the travel of said rods over the inclines 2, supposingthe engine tobe moving in the direction of the arrow.- It will, of

course, be understood that a suitable mechanism for looking or fasteningthe lever in any position to which it is adjusted should be employed 5and it will also be understood that other devices, which will readilysuggest them selves, may be employed for regulating the position of thevalves and the cut-off, in lieu of the special means herein shown.

The operation of the engine is as follows-z To distinguish between thedifferent pairs of cyl-- inders I have marked them 5, 6, 7, 8. We willsuppose steam to be let on and the engine to be moving in the directionof the arrow. The piston-rods of cylinders 5 have completed aboutone-half their stroke. Steam is still on tering these cylinders, and isalso admitted to cylinders 11, whose piston-rods, however, are still incontact with the faces 1, and consequent ly cannot yet move outwardly,although they are prepared to do so as soon as they reach the beginningof the next incline 2. The cylinders 7 and 8 are exhausting, as shown.The pistonrods of 7 are being pushed in by-ascending the inclines 4while the piston-rods of 8 are traveling over the faces 3, and,consequently, as yet have notbeenmovedinwardly. Bythetime cylinders 5have accomplished, say, three-fourths of their stroke steam is cut offfrom them, and at about the same time cylinders 6 reach their inclines2, and their pistons at once move outwardly, and thus for a portion ofthe time the engine is receiving the impulse of two pairs of cylinders.When cylinders 5 complete their stroke they commence to exhaust, andcylinders 7 will by this time have reached faces 1. Steam will then beadmitted to them, and their action with relation to cylinders 6 will bethe same as that of the latter with relation to cylinders 5. v Theoperation of the engine will, from the foregoing, be readily understood.

Having now described my invention and the manner in which the same is ormay be carried into effect, I would say, in conclusion, that 1 do notlimit myself to the precise details herein described, as the same may bevaried to a considerable extent without departure from the principle ofmy invention but What I claim, and desire to secure by Letters Patent,is

1. The combination, with a stationary case provided with a series offaces and inclines, as described, of a series of steam-cylinders carriedby and radiating from a rotary hub or steam-chest whose axis ofrevolution. is the center of the stationary case, said cylindersreceivin g steam at their inner ends and containing pistons providedwith piston-rods adapted to Work against the faces and inclines of thestationary case, at the times and in the manner substantially as shownand set forth.

2. In combination with the rotary hub or steam-chest, the stationaryvalves located within the same and arranged to admit steam into andexhaust it from the cylinders carried by said hub or steam-chest,substantially in the manner and for the purposes set forth.

3. In combination with the elements named in the preceding clause, thecentral exhaust and steam-admission pipes, under the arrangement and foroperation substantially as shown and set forth. 7

4. The arrangement of the valves in pairs, each pair being supportedupon and communicating through an exhaust-passage with a tubular stemradiating from and opening into the central exhaust-pipe, substantiallyas shown and described.

' 5. The arrangement of the valves upon a central stem capable of beingrota-ted to shift the position of said valves in relation to thecylinder-ports, in order to reverse the engine or to regulate at willthe cut-off, substantially as shown and set forth.

In testimony whereof I have signed my name to this specification beforetwo subscribing witmesses. i

HENRY TAYLOR.

Witnesses:

EDM. F. BROWN, M. BAILEY.

